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Estudo de uma técnica para o tratamento de dead-times em operações de rastreamento de objetos por servovisão
(Universidade Federal de São Carlos, 2014-05-22) Saqui, Diego; Kato, Edilson Reis Rodrigues; https://lattes.cnpq.br/8517698122676145; https://lattes.cnpq.br/4408364907687419
Visual servoing is a technique that uses computer vision to acquire visual information (by camera) and a control system with closed loop circuit to control robots. One typical application of visual servoing is tracking objects on conveyors in industrial environments. Visual servoing has the advantage of obtaining a large amount of information from the environment and greater flexibility in operations than other types of sensors. A disadvantage are the delays, known as dead-times or time-delays that can occur during the treatment of visual information in computer vision tasks or other tasks of the control system that need large processing capacity. The dead-times in visual servoing applied in industrial operations such as in the tracking of objects on conveyors are critical and can negatively affect production capacity in manufacturing environments. Some methodogies can be found in the literature for this problem and some of these methodologies are often based on the Kalman filter. In this work a technique was selected based on the formulation of the Kalman filter that already had a study on the prediction of future pose of objects with linear motion. This methodology has been studied in detail, tested and analyzed through simulations for other motions and some applications. Three types of experiments were generated: one for different types of motions and two others applied in different types of signals in the velocity control systems. The results from the motion of the object shown that the technique is able to estimate the future pose of objects with linear motion and smooth curves, but it is inefficient for drastic changes in motion. With respect to the signal to be filtered in the velocity control, the methodogy has been shown applicable (with motions conditions) only in the estimation of pose of the object after the occurrence of dead-times caused by computer vision and this information is subsequently used to calculate the future error of the object related to the robotic manipulator used to calculate the velocity of the robot. The trying to apply the methodogy directly on the error used to calculate the velocity to be applied to the robot did not produce good results. With the results the methodogy can be applied for object tracking with linear motion and smooth curves as in the case of objects transported by conveyors in industrial environments.
Acessibilidade em edifícios públicos de cultura em uma cidade de médio porte do estado de São Paulo
(Universidade Federal de São Carlos, 2014-05-22) Gomes, Luciene; Emmel, Maria Luisa Guillaumon; https://lattes.cnpq.br/5418413784503467
Since diversity is a characteristic of human beings, a crucial feature of any environment, space or object intended for use by anyone is accessibility. The city has to accommodate these differences and be adapted architectonically to enable the integration of all its dwellers. The idea driving this project is the belief that architectural planning is a potential ally in furthering the social inclusion of people with a disability or reduced mobility. This study thus deals with issues related to their access to cultural facilities, particularly by raising questions concerning the specific legislation and technical standards created to help people with disabilities. Specifically, the aim was to analyze accessibility in seven municipal cultural institutions in São Carlos city in upstate São Paulo, two of which are in outlying municipal districts. Public cultural buildings were chosen for study in the belief that a person with disability should have the same opportunities to participate in cultural life as any other person, thus becoming integrated into society. Cultural spaces should be duly adapted and accessible to the various forms of perception, locomotion and communication characteristic of an inclusive society. All cultural buildings in the chosen area were visited and, using a checklist stipulated by the Brazilian Association of Technical Standards (NBR 9050, 2004), the public spaces were classed as adequate or inadequate with respect to their accessibility to people with a disability (either visual or physical).The data collected was subjected to quantitative analysis by scoring the commonest accessibility resources, according to their adequacy, as well as the resources not installed. The results show that in all the items analysed, both in the internal and external spaces of the buildings under study, there is a need for adaptations, installations or the building of equipment that allows the physically or visually disabled to interact with the environment in the cultural spaces they choose. By indicating the state of the art in the chosen city, this study contributed to the body of knowledge in the area of accessibility.
Uma arquitetura para promover o uso de dispositivos com limitações computacionais na interação com mídias sintetizadas remotamente
(Universidade Federal de São Carlos, 2014-05-22) Godoy, Arthur Pedro de; Teixeira, Cesar Augusto Camillo; https://lattes.cnpq.br/1123376648713853; https://lattes.cnpq.br/6170705791509069
Computer graphics and virtual reality technologies allow audiovisual experiences with high level of realism, as the ones achieved in video games and movies. The synthetization of media with high degree of audiovisual realism demands specialized systems with high performance computing capacity. The profusion in the last decade of personal computing consumer electronics such as mobile and portable devices, encourages the interest in making possible, also in these devices, applications with high level of visual realism. However, due to the intrinsic limitations of the computing capability of mobile and portable devices, regarding to the physical characteristics of these devices, such as dimensions, electrical consume and heat dissipation, it s not possible directly process media with the same level of visual realism that is found in specialized systems. This research suggests the exploration of a traditional solution: the remote interaction with these applications. Challenges resulting from this approach are identified and studied. Solutions are proposed, analyzed and formalized in a architecture for reference. As a proof of concept the architecture is used in the development of applications on two scenarios: one in a local network with a media characterized by its low tolerance in delay of interaction response and another with a high tolerance media through the Internet. Also is showed the flexibility of the proposed architecture by integrating one of the applications developed with a multimedia context.
Gradiente ambiental e peixes de riachos de cabeceira da Mata Atlântica (SP)
(Universidade Federal de São Carlos, 2014-05-22) Mello, Bruno José Gomes; Cetra, Maurício; https://lattes.cnpq.br/6775493342513120; https://lattes.cnpq.br/7167845864902922
The growing interest in studies of functional diversity allows to address the relationship between the functional characteristics of species with variations in the environment attempt to understand the organization of biological communities. We examined the relationship between physical and structural characteristics of 19 stretches of headwater streams in the Atlantic Forest and morphological characteristics related to swimming ability of fish species. The environment was described by altitude, distance from species pool, substrate composition and depth of the channel. The functional characteristics were described by 11 morphological measurements. The RLQ analysis was used and the first two axes explained 97.8% of the total variation. The first axis was interpreted as the action of the altitudinal/longitudinal gradient in the structuring of assemblies of fish which varied with morphological measurements of length of caudal fin and caudal peduncle. We can say that there are two distinct assemblies positioned at the extremes of the environmental gradient separated by capacity of swimming of the species. Within these groups we can say that on a local scale the physical structure of the channel generates subgroups related to the use of the niche, suggesting the action of environmental filters. Thus, we present evidence that environmental attributes of headwaters of the Atlantic Forest are related to the structure of the assemblies of fishes that inhabit these environments.